Techniques for adjusting an optical beam trajectory

ABSTRACT

A system and method including, receiving a plurality of optical beams in a first direction along a first plane in a first beam pattern towards an optical element based on a trajectory that causes at least a portion of the plurality of optical beams to not contact a surface of the optical lens. The system and method includes transmitting a first set of the plurality of optical beams in the first direction along a second plane. The system and method includes transmitting a second set of the plurality of optical beams in the first direction along the first plane. The system and method includes generating a second beam pattern by transmitting the first set and the second set of the plurality of optical beams through an optical element, wherein the second beam pattern adjusts the trajectory to cause the portion to contact the surface of the optical lens.

RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.17/510,880, filed on Oct. 26, 2021, the entire contents of which isincorporated herein by reference in its entirety.

TECHNICAL FIELD

The present disclosure relates generally to optical beam patterns, andmore particularly to systems and methods for transforming a linearco-planar optical beam pattern into a multi-planar optical beam pattern.

BACKGROUND

Conventional light detection and ranging (LIDAR) systems operate bysending pulses toward a target and measuring the time the pulses take toreach the target and return to a sensor. In such systems, the userlearns information about the distance to the object, which when coupledwith a scanner can provide a 3-D point cloud of the sensor'sfield-of-view. These conventional techniques require more space in anoptical assembly due to physical specifications which in turn can causeless desirable beam patterns.

SUMMARY

One aspect disclosed herein is directed to a method for transforming alinear co-planar optical beam pattern into a multi-planar optical beampattern. In some embodiments, the method includes receiving (e.g.,obtaining, acquiring), by an optical assembly, a plurality of opticalbeams propagating in a first direction along a first plane in aco-planar beam pattern. In some embodiments, the method includesredirecting (e.g., sending, scattering, forwarding, relaying), by theoptical assembly, a first set of the plurality of optical beams topropagate in the first direction along a second plane. In someembodiments, the method includes redirecting, by the optical assembly, asecond set of the plurality of optical beams to propagate in a seconddirection along the first plane. In some embodiments, the methodincludes redirecting, by the optical assembly, the second set of theplurality of optical beams propagating in the second direction along thefirst plane to propagate in the first direction along the first plane.In some embodiments, the method includes generating (e.g., producing,constructing), by the optical assembly, a multi-planar beam pattern byforwarding the first set of the plurality of optical beams and thesecond set of the plurality of optical beams through an optical element

In another aspect, the present disclosure is directed to a system fortransforming a linear co-planar optical beam pattern into a multi-planaroptical beam pattern. In some embodiments, the system includes anoptical source to generate a plurality of optical beams that propagatein a first direction along a first plane in a coplanar beam pattern. Insome embodiments, the system includes an optical assembly coupled to theoptical source. In some embodiments, the optical assembly includes oneor more optical elements to receive the plurality of optical beams. Insome embodiments, the optical assembly includes one or more opticalelements to redirect a first set of the plurality of optical beams topropagate in the first direction along a second plane. In someembodiments, the optical assembly includes one or more optical elementsto redirect a second set of the plurality of optical beams to propagatein a second direction along the first plane. In some embodiments, theoptical assembly includes one or more optical elements to redirect thesecond set of the plurality of optical beams propagating in the seconddirection along the first plane to propagate in the first directionalong the first plane. In some embodiments, the optical assemblyincludes one or more optical elements to generate a multi-planar beampattern by forwarding the first set of the plurality of optical beamsand the second set of the plurality of optical beams through an opticalelement.

In another aspect, the present disclosure is directed to an opticalassembly for transforming a linear co-planar optical beam pattern into amulti-planar optical beam pattern. In some embodiments, the opticalassembly includes a first optical element to receive a first set of aplurality of optical beams. In some embodiments, the plurality ofoptical beams propagate in a first direction along a first plane in acoplanar beam pattern. In some embodiments, the optical assemblyincludes a first optical element that is configured to redirect thefirst set of the plurality of optical beams to propagate in the firstdirection along a second plane. In some embodiments, the first opticalelement is configured to forward the first set of the plurality ofoptical beams through an optical element. In some embodiments, theoptical assembly includes a second optical element that is configured toreceive a second set of the plurality of optical beams. In someembodiments, the second optical element is configured to redirect thesecond set of the plurality of optical beams to propagate in the seconddirection along the first plane. In some embodiments, the second opticalelement is configured to redirect the second set of the plurality ofoptical beams propagating in the second direction along the first planeto propagate in the first direction along the first plane. In someembodiments, the second optical element is configured to forward thesecond set of the plurality of optical beams through the opticalelement. In some embodiments, a multi-planar beam pattern is generatedresponsive to the forwarding of the first set of the plurality ofoptical beams through the optical element by the first optical elementand the forwarding of the second set of the plurality of optical beamsthrough the optical element.

These and other features, aspects, and advantages of the presentdisclosure will be apparent from a reading of the following detaileddescription together with the accompanying figures, which are brieflydescribed below. The present disclosure includes any combination of two,three, four or more features or elements set forth in this disclosure,regardless of whether such features or elements are expressly combinedor otherwise recited in a specific example implementation describedherein. This disclosure is intended to be read holistically such thatany separable features or elements of the disclosure, in any of itsaspects and example implementations, should be viewed as combinableunless the context of the disclosure clearly dictates otherwise.

It will therefore be appreciated that this summary is provided merelyfor purposes of summarizing some example implementations so as toprovide a basic understanding of some aspects of the disclosure.Accordingly, it will be appreciated that the above described exampleimplementations are merely examples and should not be construed tonarrow the scope or spirit of the disclosure in any way. Other exampleimplementations, aspects, and advantages will become apparent from thefollowing detailed description taken in conjunction with theaccompanying figures which illustrate, by way of example, the principlesof some described example implementations.

BRIEF DESCRIPTION OF THE FIGURE(S)

Embodiments and implementations of the present disclosure will beunderstood more fully from the detailed description given below and fromthe accompanying drawings of various aspects and implementations of thedisclosure, which, however, should not be taken to limit the disclosureto the specific embodiments or implementations, but are for explanationand understanding only.

FIG. 1 is a block diagram illustrating an example of a LIDAR system,according to some embodiments;

FIG. 2 is a time-frequency diagram illustrating an example of an FMCWscanning signal that can be used by a LIDAR system to scan a targetenvironment, according to some embodiments;

FIG. 3 is a block diagram illustrating an example environment fortransforming a linear co-planar optical beam pattern into a multi-planaroptical beam pattern, according to some embodiments;

FIG. 4 is a block diagram illustrating an example environment fortransforming a linear co-planar optical beam pattern into a multi-planaroptical beam pattern, according to some embodiments; and

FIG. 5 is a flow diagram illustrating an example method for transforminga linear co-planar optical beam pattern into a multi-planar optical beampattern, according to some embodiments.

DETAILED DESCRIPTION

According to some embodiments, the described LIDAR system describedherein may be implemented in any sensing market, such as, but notlimited to, transportation, manufacturing, metrology, medical, virtualreality, augmented reality, and security systems. According to someembodiments, the described LIDAR system is implemented as part of afront-end of frequency modulated continuous-wave (FMCW) device thatassists with spatial awareness for automated driver assist systems, orself-driving vehicles.

LIDAR systems use tunable lasers for frequency-chirped illumination oftargets, and coherent receivers for detection of backscattered orreflected light from the targets that are combined with a local copy ofthe transmitted signal (LO signal). Conventional LIDAR systems requirehigh frame rates and an increased number of scanning points typicallyachieved by using a photonic integrated circuit (PIC) that generates andtransmits a plurality of optical beams in a linear co-planar pattern(e.g., array), where the optical beams are separated from another bysome distance, referred to as pitch. The LIDAR system transmits theoptical beams in the linear co-planar pattern through a single outputlens that provides angular separation between collimated optical beamsto create discrete lines after reaching the scanner of the LIDAR system.By using a single output lens for multiple optical beams, the LIDARdesigner may reduce the cost of the form factor of the LIDAR system incomparison to adding additional output lenses.

However, as more optical beams are added to the LIDAR system using asingle output lens, the dimensions (e.g., a height, a width, a length,and/or a diameter) of the linear co-planar pattern of the optical beamswill eventually exceed the dimensions of the output lens; therebypreventing the optical beams from being able to simultaneously passthrough the lens without obstruction.

Accordingly, the present disclosure addresses the above-noted and otherdeficiencies by disclosing systems and methods for transforming a linearco-planar optical beam pattern into a multi-planar optical beam pattern.As described in the below passages with respect to one or moreembodiments, an optical assembly (e.g., an enclosure or an unenclosedenvironment) receives a plurality of optical beams from one or moreoptical beam sources that are included or associated (e.g., controlledby, triggered by) with the LIDAR system 100 in FIG. 1 , such as aphotonic integrated circuit (PIC) that generates and transmits aplurality of optical beams toward the optical assembly. Each beam of theplurality of optical beams is propagating (e.g., traversing) in a firstdirection (e.g., X-axis) along a first plane, such to form a linearcoplanar beam pattern (e.g., [1, N] array, where N is the number ofoptical beams in the pattern). The optical assembly redirects a firstset (e.g., one or more) of the plurality of optical beams to propagatein the first direction along a second plane. The optical assemblyredirects a second set (e.g., one or more) of the plurality of opticalbeams to propagate in a second direction along the first plane. Theoptical assembly redirects the second set of the plurality of opticalbeams that are propagating in the second direction along the first planeto propagate in the first direction along the first plane. The opticalassembly generates a multi-planar beam pattern (e.g., [2, ½×N] array,where N is the number of optical beams in the pattern) by forwarding thefirst set of the plurality of optical beams and the second set of theplurality of optical beams through an optical element (e.g., a lens).

When the plurality of optical beams is arranged in a linear co-planarbeam pattern, they cannot fit within the dimensions of the lens becausethe dimensions (e.g., a height, a width, a length, and/or a diameter) ofthe linear co-planar pattern exceeds the dimensions of the lens.However, the optical assembly's transformation of the plurality ofoptical beams from a linear co-planar beam pattern to a multi-planarbeam pattern allows the plurality of optical beams to fit within thedimensions of the lens; thereby allowing the plurality of optical beamsto simultaneously pass through the lens without obstruction.

There are several advantages for using the one or more embodiments ofthe present disclosure for transforming a linear co-planar optical beampattern into a multi-planar optical beam pattern. For one, thedimensions of a multi-planar optical beam pattern occupy less spacewithin the optical assembly as compared to the dimensions of a linearco-planar beam pattern. By occupying less space, the optical assemblymay use a smaller window for passing the plurality of optical beams to alens. The dimensions of the lens may also be reduced without interferingwith the passing of the plurality of optical beams through the lens.Using a multi-planar optical beam pattern, instead of a linear co-planarbeam pattern also allows for creating asymmetric (e.g., irregular,uneven) vertical beam spacing because, for example, the square shape ofa 2×2 multi-planar optical beam pattern can be rotated to tune beamspacing for the center 2 beams and the outside 2 beams.

FIG. 1 is a block diagram illustrating an example of a LIDAR system,according to some embodiments. The LIDAR system 100 includes one or moreof each of a number of components, but may include fewer or additionalcomponents than shown in FIG. 1 . One or more of the components depictedin FIG. 1 can be implemented on a photonics chip, according to someembodiments. The optical circuits 101 may include a combination ofactive optical components and passive optical components. Active opticalcomponents may generate, amplify, and/or detect optical signals and thelike. In some examples, the active optical component includes opticalbeams at different wavelengths, and includes one or more opticalamplifiers, one or more optical detectors, or the like. In someembodiments, one or more LIDAR systems 100 may be mounted onto any area(e.g., front, back, side, top, bottom, and/or underneath) of a vehicleto facilitate the detection of an object in any free-space relative tothe vehicle. In some embodiments, the vehicle may include a steeringsystem and a braking system, each of which may work in combination withone or more LIDAR systems 100 according to any information (e.g.,distance/ranging information, Doppler information, etc.) acquired and/oravailable to the LIDAR system 100. In some embodiments, the vehicle mayinclude a vehicle controller that includes the one or more componentsand/or processors of the LIDAR system 100.

Free space optics 115 may include one or more optical waveguides tocarry optical signals, and route and manipulate optical signals toappropriate input/output ports of the active optical circuit. Inembodiments, the one or more optical waveguides may include one or moregraded index waveguides, as will be described in additional detail belowat FIGS. 3-6 . The free space optics 115 may also include one or moreoptical components such as taps, wavelength division multiplexers (WDM),splitters/combiners, polarization beam splitters (PBS), collimators,couplers or the like. In some examples, the free space optics 115 mayinclude components to transform the polarization state and directreceived polarized light to optical detectors using a PBS, for example.The free space optics 115 may further include a diffractive element todeflect optical beams having different frequencies at different anglesalong an axis (e.g., a fast-axis).

In some examples, the LIDAR system 100 includes an optical scanner 102that includes one or more scanning mirrors that are rotatable along anaxis (e.g., a slow-axis) that is orthogonal or substantially orthogonalto the fast-axis of the diffractive element to steer optical signals toscan an environment according to a scanning pattern. For instance, thescanning mirrors may be rotatable by one or more galvanometers. Objectsin the target environment may scatter an incident light into a returnoptical beam or a target return signal. The optical scanner 102 alsocollects the return optical beam or the target return signal, which maybe returned to the passive optical circuit component of the opticalcircuits 101. For example, the return optical beam may be directed to anoptical detector by a polarization beam splitter. In addition to themirrors and galvanometers, the optical scanner 102 may includecomponents such as a quarter-wave plate, lens, anti-reflective coatedwindow or the like.

To control and support the optical circuits 101 and optical scanner 102,the LIDAR system 100 includes LIDAR control systems 110. The LIDARcontrol systems 110 may include a processing device for the LIDAR system100. In some examples, the processing device may be one or moregeneral-purpose processing devices such as a microprocessor, centralprocessing unit, or the like. More particularly, the processing devicemay be complex instruction set computing (CISC) microprocessor, reducedinstruction set computer (RISC) microprocessor, very long instructionword (VLIW) microprocessor, or processor implementing other instructionsets, or processors implementing a combination of instruction sets. Theprocessing device may also be one or more special-purpose processingdevices such as an application specific integrated circuit (ASIC), afield programmable gate array (FPGA), a digital signal processor (DSP),network processor, or the like.

In some examples, the LIDAR control system 110 may include a processingdevice that may be implemented with a DSP, such as signal processingunit 112. The LIDAR control systems 110 are configured to output digitalcontrol signals to control optical drivers 103. In some examples, thedigital control signals may be converted to analog signals throughsignal conversion unit 106. For example, the signal conversion unit 106may include a digital-to-analog converter. The optical drivers 103 maythen provide drive signals to active optical components of opticalcircuits 101 to drive optical sources such as lasers and amplifiers. Insome examples, several optical drivers 103 and signal conversion units106 may be provided to drive multiple optical sources.

The LIDAR control systems 110 are also configured to output digitalcontrol signals for the optical scanner 102. A motion control system 105may control the galvanometers of the optical scanner 102 based oncontrol signals received from the LIDAR control systems 110. Forexample, a digital-to-analog converter may convert coordinate routinginformation from the LIDAR control systems 110 to signals interpretableby the galvanometers in the optical scanner 102. In some examples, amotion control system 105 may also return information to the LIDARcontrol systems 110 about the position or operation of components of theoptical scanner 102. For example, an analog-to-digital converter may inturn convert information about the galvanometers' position to a signalinterpretable by the LIDAR control systems 110.

The LIDAR control systems 110 are further configured to analyze incomingdigital signals. In this regard, the LIDAR system 100 includes opticalreceivers 104 to measure one or more beams received by optical circuits101. For example, a reference beam receiver may measure the amplitude ofa reference beam from the active optical component, and ananalog-to-digital converter converts signals from the reference receiverto signals interpretable by the LIDAR control systems 110. Targetreceivers measure the optical signal that carries information about therange and velocity of a target in the form of a beat frequency,modulated optical signal. The reflected beam may be mixed with a secondsignal from a local oscillator. The optical receivers 104 may include ahigh-speed analog-to-digital converter to convert signals from thetarget receiver to signals interpretable by the LIDAR control systems110. In some examples, the signals from the optical receivers 104 may besubject to signal conditioning by signal conditioning unit 107 prior toreceipt by the LIDAR control systems 110. For example, the signals fromthe optical receivers 104 may be provided to an operational amplifierfor amplification of the received signals and the amplified signals maybe provided to the LIDAR control systems 110.

In some applications, the LIDAR system 100 may additionally include oneor more imaging devices 108 configured to capture images of theenvironment, a global positioning system 109 configured to provide ageographic location of the system, or other sensor inputs. The LIDARsystem 100 may also include an image processing system 114. The imageprocessing system 114 can be configured to receive the images andgeographic location, and send the images and location or informationrelated thereto to the LIDAR control systems 110 or other systemsconnected to the LIDAR system 100.

In operation according to some examples, the LIDAR system 100 isconfigured to use nondegenerate optical sources to simultaneouslymeasure range and velocity across two dimensions. This capability allowsfor real-time, long range measurements of range, velocity, azimuth, andelevation of the surrounding environment.

In some examples, the scanning process begins with the optical drivers103 and LIDAR control systems 110. The LIDAR control systems 110instruct, e.g., via signal processing unit 112, the optical drivers 103to independently modulate one or more optical beams, and these modulatedsignals propagate through the optical circuits 101 to the free spaceoptics 115. The free space optics 115 directs the light at the opticalscanner 102 that scans a target environment over a preprogrammed patterndefined by the motion control system 105. The optical circuits 101 mayalso include a polarization wave plate (PWP) to transform thepolarization of the light as it leaves the optical circuits 101. In someexamples, the polarization wave plate may be a quarter-wave plate or ahalf-wave plate. A portion of the polarized light may also be reflectedback to the optical circuits 101. For example, lensing or collimatingsystems used in LIDAR system 100 may have natural reflective propertiesor a reflective coating to reflect a portion of the light back to theoptical circuits 101.

Optical signals reflected back from an environment pass through theoptical circuits 101 to the optical receivers 104. Because thepolarization of the light has been transformed, it may be reflected by apolarization beam splitter along with the portion of polarized lightthat was reflected back to the optical circuits 101. In such scenarios,rather than returning to the same fiber or waveguide serving as anoptical source, the reflected signals can be reflected to separateoptical receivers 104. These signals interfere with one another andgenerate a combined signal. The combined signal can then be reflected tothe optical receivers 104. Also, each beam signal that returns from thetarget environment may produce a time-shifted waveform. The temporalphase difference between the two waveforms generates a beat frequencymeasured on the optical receivers 104 (e.g., photodetectors).

The analog signals from the optical receivers 104 are converted todigital signals by the signal conditioning unit 107. These digitalsignals are then sent to the LIDAR control systems 110. A signalprocessing unit 112 may then receive the digital signals to furtherprocess and interpret them. In some embodiments, the signal processingunit 112 also receives position data from the motion control system 105and galvanometers (not shown) as well as image data from the imageprocessing system 114. The signal processing unit 112 can then generate3D point cloud data (sometimes referred to as, “a LIDAR point cloud”)that includes information about range and/or velocity points in thetarget environment as the optical scanner 102 scans additional points.In some embodiments, a LIDAR point cloud may correspond to any othertype of ranging sensor that is capable of Doppler measurements, such asRadio Detection and Ranging (RADAR). The signal processing unit 112 canalso overlay 3D point cloud data with image data to determine velocityand/or distance of objects in the surrounding area. The signalprocessing unit 112 also processes the satellite-based navigationlocation data to provide data related to a specific global location.

FIG. 2 is a time-frequency diagram illustrating an example of an FMCWscanning signal that can be used by a LIDAR system to scan a targetenvironment, according to some embodiments. In one example, the scanningwaveform 201, labeled as f_(FM)(t), is a sawtooth waveform (sawtooth“chirp”) with a chirp bandwidth Δf_(C) and a chirp period T_(C). Theslope of the sawtooth is given as k=(Δf_(C)/T_(C)). FIG. 2 also depictstarget return signal 202 according to some embodiments. Target returnsignal 202, labeled as f_(FM)(t−Δt), is a time-delayed version of thescanning waveform 201, where Δt is the round trip time to and from atarget illuminated by scanning waveform 201. The round trip time isgiven as Δt=2R/v, where R is the target range and v is the velocity ofthe optical beam, which is the speed of light c. The target range, R,can therefore be calculated as R=c(Δt/2). When the return signal 202 isoptically mixed with the scanning signal, a range-dependent differencefrequency (“beat frequency”) Δf_(R)(t) is generated. The beat frequencyΔf_(R)(t) is linearly related to the time delay Δt by the slope of thesawtooth k. That is, Δf_(R)(t)=kΔt. Since the target range R isproportional to Δt, the target range R can be calculated asR=(c/2)(Δf_(R)(t)/k). That is, the range R is linearly related to thebeat frequency Δf_(R)(t). The beat frequency Δf_(R)(t) can be generated,for example, as an analog signal in optical receivers 104 of system 100.The beat frequency can then be digitized by an analog-to-digitalconverter (ADC), for example, in a signal conditioning unit such assignal conditioning unit 107 in LIDAR system 100. The digitized beatfrequency signal can then be digitally processed, for example, in asignal processing unit, such as signal processing unit 112 in system100. It should be noted that the target return signal 202 will, ingeneral, also includes a frequency offset (Doppler shift) if the targethas a velocity relative to the LIDAR system 100. The Doppler shift canbe determined separately, and used to correct (e.g., adjust, modify) thefrequency of the return signal, so the Doppler shift is not shown inFIG. 2 for simplicity and ease of explanation. For example, LIDAR system100 may correct the frequency of the return signal by removing (e.g.,subtracting, filtering) the Doppler shift from the frequency of thereturned signal to generate a corrected return signal. The LIDAR system100 may then use the corrected return signal to calculate a distanceand/or range between the LIDAR system 100 and the object. In someembodiments, the Doppler frequency shift of target return signal 202that is associated with an object may be indicative of a velocity and/ormovement direction of the object relative to the LIDAR system 100.

It should also be noted that the sampling frequency of the ADC willdetermine the highest beat frequency that can be processed by the systemwithout aliasing. In general, the highest frequency that can beprocessed is one-half of the sampling frequency (i.e., the “Nyquistlimit”). In one example, and without limitation, if the samplingfrequency of the ADC is 1 gigahertz, then the highest beat frequencythat can be processed without aliasing (Δf_(Rmax)) is 500 megahertz.This limit in turn determines the maximum range of the system asR_(max)=(c/2)(Δf_(Rmax)/k) which can be adjusted by changing the chirpslope k. In one example, while the data samples from the ADC may becontinuous, the subsequent digital processing described below may bepartitioned into “time segments” that can be associated with someperiodicity in the LIDAR system 100. In one example, and withoutlimitation, a time segment might correspond to a predetermined number ofchirp periods T, or a number of full rotations in azimuth by the opticalscanner.

FIG. 3 is a block diagram illustrating an example environment fortransforming a linear co-planar optical beam pattern into a multi-planaroptical beam pattern, according to some embodiments. The environment 300includes an optical element 310 (sometimes referred to as, “a verticalprism” or “first optical element”) and an optical element 320 (sometimesreferred to as, “a horizontal prism” or “second optical element”), thatare each configured to receive at least one optical beam that ispropagating in a direction along a plane and redirect (e.g., steer) theat least one optical beam into the same or different direction and/oronto the same plane or a different plane. In some embodiments, opticalelements 310, 320 may each be any type of mirror (e.g., a polygonmirror). In some embodiments, optical elements 310, 320 may each be anytype of prism including, but not limited to, a Risley prism, a wedgeprism, a polygonal prism, pentagonal prism, a dove prism, a halfpentagonal prism, a right angle prism, a roof prism, or the like.

The environment 300 includes a lens 330 (sometimes referred to as,“optical element”) for receiving optical beams from the optical element310 and/or optical element 320, sending the optical beams intofree-space toward one or more objects (e.g., pedestrians, vehicles,street surface, street signs, raindrops, etc.), and collecting thereturned optical beams that scatter from the one or more objects. Insome embodiments, the lens 330 may be a symmetric lens having a diameter(e.g., 10 mm-40 mmm). In some embodiments, the lens 330 may be anasymmetric lens. In some embodiments, the lens 330 may be any shape,such as, a square, a rectangle, a circle, an oval, etc.

The environment 300 shows the reception and redirection of the opticalbeams by the optical elements 310, 320 from a “side view” with respectto an X-Z axis, “a pattern view” with respect to a Y-Z axis, and “a topview” with respect to an X-Y axis. Each view shows the optical beampattern of the optical beams at three distances from the lens 330, suchas location 1 (shown in FIG. 3 as “Loc1”), location 2 (shown in FIG. 3as “Loc2”), and location 3 (shown in FIG. 3 as “Loc3”). In this example,location 1 is the farthest distance from the lens 330 and location 3 isthe closest distance to the lens 330. As indicated by the direction ofthe arrow of the pattern viewing direction in FIG. 3 , the pattern viewshows the optical beam pattern of the optical beams 311, 312, 313, 314at locations 1, 2, and 3 when looking into the optical beams 311, 312,313, 314.

In some embodiments, one or more optical beam sources (not shown in FIG.3 ) may generate the optical beams 311, 312, 313, 314 (sometimesreferred to as, “a plurality of optical beams”) to form the optical beampattern at location 1 in FIG. 3 . As shown in the pattern view in FIG. 3, the arrangement of the optical beams 311, 312, 313, 314 form a linear,co-planar pattern, such that the optical beams 311, 312, 313, 314 haveno offset (or a negligible offset) from one another along the Z-axis. Insome embodiments, the optical beams 311, 312, 313, 314 are symmetrically(e.g., even) spaced apart from one another along the Y-axis. In someembodiments, the optical beams 311, 312, 313, 314 are asymmetrically(e.g., uneven) spaced apart from one another along the Y-axis.

In some embodiments, the optical beams 311, 312, 313, 314 may begenerated by one or more optical beam sources that are included orassociated (e.g., controlled by, triggered by) with the LIDAR system 100in FIG. 1 , such as a photonic integrated circuit (PIC). In someembodiments, the LIDAR control system 110 in FIG. 1 may control the PICto cause the PIC to generate and transmit optical beams. In someembodiments, the PIC may include a plurality of output ports (e.g.,channels, pins) that are arranged on the same side of the PIC in alinear coplanar pattern. In some embodiments, the PIC may transmit theoptical beams 311, 312, 313, 314 toward the optical elements 310, 320through its plurality of output ports to form the optical beam patternat location 1 in FIG. 3 .

In some embodiments, the one or more optical beam sources may beconfigured to transmit (e.g., direct) the optical beams 311, 312(sometimes referred to as, “a first set of a plurality of opticalbeams”) toward the optical element 310 and the optical beams 313, 314(sometimes referred to as, “a second set of a plurality of opticalbeams”) toward the optical element 320. In some embodiments, thetransmission of the optical beams 311, 312, 313, 314 causes each beam topropagate (e.g., traverse) in a first direction along a first plane(e.g., along the X-axis), such to form a linear coplanar beam pattern.In some embodiments, a linear coplanar beam pattern may be 1 row ofoptical beams times N, where N is the number of optical beams in theoptical beam pattern. For example, a linear coplanar beam pattern mayinclude a row of any number of optical beams from 1 to 64.

In some embodiments, the one or more optical beam sources may eachgenerate an optical beam of any wavelength (e.g., 905 nanometer (nm),1550 nm) to cause the optical beam pattern at each of the locations(e.g., location 1, location 2, and location 3) to include optical beamsof the same wavelength or different wavelengths. For example, the one ormore optical beam sources may generate a plurality of optical beams thatinclude a first subset of optical beams that have a wavelength of 905 nmto detect objects of a first type (e.g., water, rain and fog, and snow),and a second subset of optical beams that have a wavelength of 1550 nmto detect objects of a second type (e.g., vehicles, street signs,pedestrian). By using an optical beam pattern that includes opticalbeams of different wavelengths, the LIDAR system 100 may detect (e.g.,identify, discover, resolve) more objects with fewer scans as comparedto scanning an environment using an optical beam pattern of a firstwavelength and re-scanning the environment using an optical beam patternof a second wavelength.

From the side view at location 1, the optical beams 311, 312, 313, 314overlap with one another along the X-axis because their separation alongthe Y-axis is not visible from the side view. From the pattern view atlocation 1, the optical beams 311, 312, 313, 314 have a linear co-planarbeam pattern. From the top view at location 1, the optical beams 311,312, 313, 314 are parallel with one another along the X-axis.

In some embodiments, the optical element 310 is configured (e.g.,arranged, positioned) to receive the optical beams 311, 312. In someembodiments, the optical element 310 is configured to redirect theoptical beams 311, 312 to propagate in the first direction along asecond plane (e.g., along the X-axis) toward the lens 330. From the sideview at location 2, the optical beams 311, 312 overlap with one anotheralong the X-axis on the second plane because their separation along theY-axis is not visible from the side view, and the optical beams 313, 314overlap with one another along the X-axis on the first plane becausetheir separation along the Y-axis is also not visible from the sideview. From the pattern view at location 2, the optical beams 311, 312have a linear co-planar beam pattern on the second plane and the opticalbeams 313, 314 have a linear co-planar beam pattern on the first plane,where the optical beams 311, 312 are shifted to the left (e.g., furtherfrom lens 330) of the optical beams 313, 314 on the Y-axis. From the topview at location 2, the optical beams 311, 312, 313, 314 are parallelwith one another along the X-axis.

In some embodiments, the optical element 310 is configured to redirectthe optical beams 311, 312 to propagate in the first direction along thesecond plane by redirecting the optical beams 311, 312 to propagate inan upward direction along a third plane (e.g., along the Z-axis). Insome embodiments, the first plane is parallel to the second plane. Insome embodiments, the first plane is not parallel to the second plane.In some embodiments, the second plane is above the first plane along theZ-axis. In some embodiments, the third plane is perpendicular to atleast one of the first plane or the second plane. In some embodiments,the third plane is not perpendicular to the first plane or the secondplane.

In some embodiments, the optical element 320 is configured to receivethe optical beams 313, 314. In some embodiments, the optical element 320is configured to redirect the optical beams 313, 314 to propagate in asecond direction (e.g., sideways) along the first plane (e.g., along theX-axis). In some embodiments, the optical element 320 is configured toredirect the optical beams 313, 314 from propagating in the seconddirection along the first plane to propagate in the first directionalong the first plane toward the lens 330. In some embodiments, theoptical element 320 is configured to shift (e.g., move) the opticalbeams 313, 314 to the left along the Y-axis to generate the multi-planarbeam pattern at location 3 in FIG. 3 . In some embodiments, amulti-planar beam pattern may be any shape, such as, a square, arhombus, a rectangle, a triangle, a circle, a trapezoid, a hexagon, anoctagon, etc.

From the side view at location 3, the optical beams 313, 314 overlapwith one another along the X-axis on the first plane because theirseparation along the Y-axis is not visible from the side view. From thepattern view at location 3, the optical beams 311, 312 have a linearco-planar beam pattern on the second plane and the optical beams 313,314 have a linear co-planar beam pattern on the first plane, where theoptical beams 311, 312, 313, 314 form a multi-planar beam pattern.

In some embodiments, optical elements 310, 320 are configured togenerate a multi-planar beam pattern by redirecting and/or forwardingthe optical beams 311, 312, 313, 314 through the lens 330. In someembodiments, the optical beams 311, 312, 313, 314 of the multi-planarbeam pattern are symmetrically (e.g., even) spaced apart from oneanother along the Y-axis and the Z-axis. In some embodiments, theoptical beams 311, 312, 313, 314 of the multi-planar beam pattern areasymmetrically (e.g., uneven) spaced apart from one another along theY-axis and the Z-axis.

In some embodiments, the dimensions (e.g., a height, a width, a length,and/or a diameter) of the linear co-planar pattern of the optical beams311, 312, 313, 314 at location 1 are incompatible with the dimensions ofthe surface area of the lens 330 such that the optical beams 311, 312,313, 314 cannot simultaneously pass through the lens 330 when arrangedin the linear co-planar pattern. For example, if the length of thelinear co-planar pattern of the optical beams 311, 312, 313, 314 atlocation 1 is greater than the dimensions (e.g., a height, a width, alength, and/or a diameter) of the lens 330, then the optical beams 311,312, 313, 314 cannot simultaneously pass through the lens 330 whenarranged in the linear co-planar pattern.

In some embodiments, the dimensions of the multi-planar pattern of theoptical beams 311, 312, 313, 314 at location 3 are compatible with thedimensions of the surface area of the lens 330 such that the opticalbeams 311, 312, 313, 314 can simultaneously pass through the lens 330when arranged in the multi-planar pattern. For example, if the length ofthe multi-planar pattern of the optical beams 311, 312, 313, 314 atlocation 3 is greater than the dimensions of the lens 330, then theoptical beams 311, 312, 313, 314 can simultaneously pass through thelens 330 when arranged in the multi-planar pattern.

Although FIG. 3 shows only a select number of optical elements (e.g.,optical element 310, optical element 320); the environment 300 mayinclude any number of optical elements in any arrangement to facilitatethe transformation of a linear co-planar optical beam pattern into amulti-planar optical beam pattern. In some embodiments, the operationsof the optical elements 310, 320 may be performed by a single opticalelement. For example, a single optical element may be configured toreceive the optical beams 311, 312, 313, 314 propagating in a firstdirection along a first plane in a linear co-planar beam pattern,redirect the optical beams 311, 312 such that they propagate in thefirst direction along a second plane, shift the optical beams 313, 314to the left on the Y-axis, and redirect the optical beams 313, 314 topropagate in the first direction along the first plane. Thus, the singleoptical element may transform the optical beams 311, 312, 313, 314 froma linear co-planar optical beam pattern into a multi-planar optical beampattern.

As shown in FIG. 3 , the optical element 310 is positioned betweenlocation 1 and location 2, and optical element 320 is positioned betweenlocation 2 and location 3. However, in some embodiments, the opticalelement 310 may be positioned between location 2 and location 3, andoptical element 320 may be positioned between location 1 and location 2without altering the operation and functionality of the optical elements310, 320. It should be appreciated that embodiments of the presentdisclosure are not limited to the number of optical elements depicted inFIG. 3 . For instance, 3 or more optical elements may be included inorder to achieve a final beam pattern and/or orientation.

FIG. 4 is a block diagram illustrating an example environment fortransforming a linear co-planar optical beam pattern into a multi-planaroptical beam pattern, according to some embodiments. The environment 400includes an enclosure 402 (sometimes referred to as, “an opticalassembly”) and the lens 330 in FIG. 3 . The environment 400 depicts theenclosure 400 and the lens 330 according to the side view in FIG. 3 ,which is with respect to the X-Z axis. The environment 400 includeslocation markers (e.g., Loc1, Loc2, Loc3) that correspond to thelocation markers in FIG. 3 .

In some embodiments, the enclosure 402 is configured to include and holdthe optical elements 310, 320 (not shown in FIG. 4 ) in FIG. 3 . In someembodiments, the enclosure 402 includes a window 404 that is configured(e.g., sized) to receive the optical beams 311, 312, 313, 314 from theone or more optical sources, as discussed herein. In some embodiments,the enclosure 402 includes a window 406 that is configured (e.g., sized)to allow the optical elements 310, 320 to transmit the optical beams311, 312, 313, 314 in a multi-planar pattern toward the lens 330.

In some embodiments, the width of the window 406 is equal to or lessthan the dimensions of the lens 330. In some embodiments, the width ofthe window 404 exceeds the width of the window 406 and/or the dimensionsof the lens 330. In some embodiments, the width of the window 406 is notlarge enough to allow the linear co-planar pattern of the optical beams311, 312, 313, 314 at location 1 to simultaneously pass through thewindow 406, but is large enough to allow the multi-planar pattern of theoptical beams 311, 312, 313, 314 at location 3 to simultaneously passthrough the window 406. In this instance, the transformation of theoptical beams 311, 312, 313, 314 by the optical elements 310, 320 from alinear co-planar pattern to a multi-planar pattern allows a LIDAR systemto be reduced (e.g., scale down). For example, the dimensions (e.g.,height, and/or width) of the window 406 of the enclosure 402 and thedimensions of the lens 330 can be reduced without degrading theperformance of the LIDAR system 100.

FIG. 5 is a flow diagram illustrating an example method for transforminga linear co-planar optical beam pattern into a multi-planar optical beampattern, according to some embodiments. Additional, fewer, or differentoperations may be performed in the method depending on the particulararrangement. In some embodiments, some or all operations of method 500may be performed by one or more processors executing on one or morecomputing devices, systems, or servers (e.g., remote/networked serversor local servers). In some embodiments, method 700 may be performed by asignal processing unit, such as signal processing unit 112 in FIG. 1 .Each operation may be re-ordered, added, removed, or repeated.

In some embodiments, the method 500 may include the operation 502 ofreceiving, by an optical assembly, a plurality of optical beamspropagating in a first direction along a first plane in a coplanar beampattern. In some embodiments, the method 500 may include the operation504 of redirecting, by the optical assembly, a first set of theplurality of optical beams to propagate in the first direction along asecond plane. In some embodiments, the method 500 may include theoperation 506 of redirecting, by the optical assembly, a second set ofthe plurality of optical beams to propagate in a second direction alongthe first plane.

In some embodiments, the method 500 may include the operation 508 ofredirecting, by the optical assembly, the second set of the plurality ofoptical beams propagating in the second direction along the first planeto propagate in the first direction along the first plane. In someembodiments, the method 500 may include the operation 510 of generating,by the optical assembly, a multi-planar beam pattern by forwarding thefirst set of the plurality of optical beams and the second set of theplurality of optical beams through an optical element.

The preceding description sets forth numerous specific details such asexamples of specific systems, components, methods, and so forth, inorder to provide a good understanding of several embodiments of thepresent disclosure. It will be apparent to one skilled in the art,however, that at least some embodiments of the present disclosure may bepracticed without these specific details. In other instances, well-knowncomponents or methods are not described in detail or are presented insimple block diagram format in order to avoid unnecessarily obscuringthe present disclosure. Thus, the specific details set forth are merelyexemplary. While this specification contains many specificimplementation details, these should not be construed as limitations onthe scope of any inventions or of what may be claimed, but rather asdescriptions of features specific to particular embodiments ofparticular inventions. Certain features that are described in thisspecification in the context of separate embodiments can also beimplemented in combination in a single embodiment. Conversely, variousfeatures that are described in the context of a single embodiment canalso be implemented in multiple embodiments separately or in anysuitable sub-combination. Moreover, although features may be describedabove as acting in certain combinations and even initially claimed assuch, one or more features from a claimed combination can in some casesbe excised from the combination, and the claimed combination may bedirected to a sub-combination or variation of a sub-combination.Moreover, the separation of various system components in the embodimentsdescribed above should not be understood as requiring such separation inall embodiments, and it should be understood that the described programcomponents and systems can generally be integrated together in a singlesoftware product or packaged into multiple software products. Particularembodiments may vary from these exemplary details and still becontemplated to be within the scope of the present disclosure.

Reference throughout this specification to “one embodiment” or “anembodiment” means that a particular feature, structure, orcharacteristic described in connection with the embodiments included inat least one embodiment. Thus, the appearances of the phrase “in oneembodiment” or “in an embodiment” in various places throughout thisspecification are not necessarily all referring to the same embodiment.In addition, the term “or” is intended to mean an inclusive “or” ratherthan an exclusive “or.”

Although the operations of the methods herein are shown and described ina particular order, the order of the operations of each method may bealtered so that certain operations may be performed in an inverse orderor so that certain operations may be performed, at least in part,concurrently with other operations. In another embodiment, instructionsor sub-operations of distinct operations may be in an intermittent oralternating manner.

The above description of illustrated implementations of the invention,including what is described in the Abstract, is not intended to beexhaustive or to limit the invention to the precise forms disclosed.While specific implementations of, and examples for, the invention aredescribed herein for illustrative purposes, various equivalentmodifications are possible within the scope of the invention, as thoseskilled in the relevant art will recognize. The words “example” or“exemplary” are used herein to mean serving as an example, instance, orillustration. Any aspect or design described herein as “example” or“exemplary” is not necessarily to be construed as preferred oradvantageous over other aspects or designs. Rather, use of the words“example” or “exemplary” is intended to present concepts in a concretefashion. As used in this application, the term “or” is intended to meanan inclusive “or” rather than an exclusive “or”. That is, unlessspecified otherwise, or clear from context, “X includes A or B” isintended to mean any of the natural inclusive permutations. That is, ifX includes A; X includes B; or X includes both A and B, then “X includesA or B” is satisfied under any of the foregoing instances. In addition,the articles “a” and “an” as used in this application and the appendedclaims should generally be construed to mean “one or more” unlessspecified otherwise or clear from context to be directed to a singularform. Moreover, use of the term “an embodiment” or “one embodiment” or“an implementation” or “one implementation” throughout is not intendedto mean the same embodiment or implementation unless described as such.Furthermore, the terms “first,” “second,” “third,” “fourth,” etc. asused herein are meant as labels to distinguish among different elementsand may not necessarily have an ordinal meaning according to theirnumerical designation.

What is claimed is:
 1. A method comprising: receiving, by an opticalassembly, a plurality of optical beams in a first direction along afirst plane in a first beam pattern towards an optical element based ona trajectory that causes at least a portion of the plurality of opticalbeams to not contact a surface of the optical lens; transmitting, by theoptical assembly, a first set of the plurality of optical beams in thefirst direction along a second plane, wherein the first plane isdifferent from the second plane; transmitting, by the optical assembly,a second set of the plurality of optical beams in the first directionalong the first plane, and generating, by the optical assembly, a secondbeam pattern by transmitting the first set of the plurality of opticalbeams and the second set of the plurality of optical beams through anoptical element, wherein the second beam pattern adjusts the trajectoryto cause the portion to contact the surface of the optical lens.
 2. Themethod of claim 1, wherein the first plane is parallel to the secondplane.
 3. The method of claim 1, further comprising: transmitting, bythe optical assembly, the second set of the plurality of optical beamsin a second direction along the first plane prior to transmitting thesecond set of the plurality of optical beams in the first directionalong the first plane.
 4. The method of claim 1, wherein the opticalassembly comprises a first optical element and a second optical elementand further comprising: transmitting, by the optical assembly, the firstset of the plurality of optical beams to propagate in the firstdirection along the second plane by using the first optical element; andtransmitting, by the optical assembly, the second set of the pluralityof optical beams to propagate in the second direction along the firstplane by using the second optical element.
 5. The method of claim 1,wherein the transmitting the first set of the plurality of optical beamsto propagate in the first direction along the second plane comprises:transmitting, by the optical assembly, the first set of the plurality ofoptical beams to propagate along a third plane.
 6. The method of claim5, wherein the third plane is perpendicular to the first plane and thesecond plane.
 7. The method of claim 1, wherein a length of the firstbeam pattern is greater than a diameter of the optical element and alength of the second beam pattern is less than the diameter of theoptical element.
 8. The method of claim 1, wherein the optical assemblyis enclosed in an enclosure comprising a window, a length of the firstbeam pattern is greater than a length of the window and a length of thesecond beam pattern is less than the length of the window.
 9. The methodof claim 1, wherein the second beam pattern comprises an asymmetricvertical beam spacing.
 10. The method of claim 1, wherein the receivingthe plurality of optical beams propagating in the first direction alongthe first plane in the first beam pattern comprises: receiving, by theoptical assembly, the plurality of optical beams via a photonicintegrated circuit (PIC).
 11. A system comprising: an optical source togenerate a plurality of optical beams that propagate in a firstdirection along a first plane in a first beam pattern towards an opticalelement based on a trajectory that causes at least a portion of theplurality of optical beams to not contact a surface of the optical lens;and an optical assembly coupled to the optical source, the opticalassembly comprising one or more optical elements to: receive theplurality of optical beams; transmit a first set of the plurality ofoptical beams in the first direction along a second plane, wherein thefirst plane is different from the second plane; transmit a second set ofthe plurality of optical beams in the first direction along the firstplane, and generate a second beam pattern by transmitting the first setof the plurality of optical beams and the second set of the plurality ofoptical beams through an optical element, wherein the second beampattern adjusts the trajectory to cause the portion to contact thesurface of the optical lens.
 12. The system of claim 11, wherein thefirst plane is parallel to the second plane.
 13. The system of claim 11,wherein the one or more optical elements further to: transmit the secondset of the plurality of optical beams in a second direction along thefirst plane prior to transmitting the second set of the plurality ofoptical beams in the first direction along the first plane.
 14. Thesystem of claim 11, wherein the first optical element is to further:transmit the first set of the plurality of optical beams to propagatealong a third plane.
 15. The system of claim 14, wherein the third planeis perpendicular to the first plane and the second plane.
 16. The systemof claim 11, wherein a length of the first beam pattern is greater thana diameter of the optical element and a length of the second beampattern is less than the diameter of the optical element.
 17. The systemof claim 11, wherein the optical assembly is enclosed in an enclosurecomprising a window, and a length of the first beam pattern is greaterthan a length of the window and a length of the second beam pattern isless than the length of the window.
 18. The system of claim 11, whereinthe second beam pattern comprises an asymmetric vertical beam spacing.19. The system of claim 11, wherein the optical assembly receives theplurality of optical beams from a photonic integrated circuit (PIC). 20.An optical assembly comprising: a first optical element to: receive afirst set of a plurality of optical beams, wherein the plurality ofoptical beams propagate in a first direction along a first plane in afirst beam pattern towards an optical element based on a trajectory thatcauses at least a portion of the first set of the plurality of opticalbeams to not contact a surface of the optical lens; transmit the firstset of the plurality of optical beams in the first direction along asecond plane, wherein the first plane is different from the secondplane; and transmit the first set of the plurality of optical beamsthrough an optical element; and a second optical element to: receive asecond set of the plurality of optical beams; transmit the second set ofthe plurality of optical beams in the first direction along the firstplane; and transmit the second set of the plurality of optical beamsthrough the optical element, wherein a second beam pattern is generatedresponsive to the transmitting of the first set of the plurality ofoptical beams through the optical element by the first optical elementand the transmitting of the second set of the plurality of optical beamsthrough the optical element, wherein the second beam pattern adjusts thetrajectory to cause the portion to contact the surface of the opticallens.